"A filter lane feels much more of a safety support than any widely ignored bit of red paint."
Isn't the point that the cycle lane is ignored *because* the filter lane pushes motorised traffic into it?
Even I drive in the cycle lane outside the Missoni, and I'm more than averagely inclined to look out for cyclists.
Or to put it another way - if the situation was reversed (think of somewhere in town with a well-observed cycle lane but people have to turn right normally), and the suggestion was made to remove the cycle lane to add a right filter, there would be a bit of an outcry.
However, I don't really know what proportion of cyclists turn right here. I perceive it as a small minority profiting at the expense (as it were) of everyone else, but it may be the other way around, in which case the filter lane over the cycle lane would be the smart option.